Numerical Study of a Novel Air Curtain Dust Isolation Device for a Fully Mechanized Roadheader Driver

The long-pressure and short-exhaust ventilation method can effectively reduce dust concentration in mine roadways (tunnels) and alleviate hazards to workers. However, it is usually difficult to resolve the problem of high dust concentrations at the driver operation area. Accordingly, this paper proposes an air curtain dust isolation device suitable for the driver operation area, and computational fluid dynamics (CFD) methods were also employed to carry out numerical simulations and parameter optimization of its dust isolation efficiency. The research findings indicate that the device creates a transparent air curtain in front of the driver, effectively preventing dust from spreading towards the driver operation area. However, its dust isolation performance was significantly affected by the jet velocity. When the jet velocity was within the range of 0–10 m/s, the dust concentration at the driver operation area increased as the velocity rose; when the jet velocity increased to 15 m/s, the dust concentration fell sharply, with the average concentrations of total dust and PM2.5 reaching the lowest values of 9.52 mg/m3 and 3.87 mg/m3, respectively. However, when the jet velocity was further increased to 20 m/s, the dust concentrations rose significantly again. Compared with conditions without an air curtain, at the optimum jet velocity of 15 m/s, the dust isolation efficiency reached 58.1%, indicating that this device can effectively safeguard the driver’s occupational health. The findings of this study may serve as a reference for dust protection at the driver operation area in similar working environments, such as tunnel excavation and metal mining.